The Lasik operation is performed with the patient awake and mobile; however,
the patient typically is given a mild sedative (such as Valium or diazepam)
and anesthetic eye drops.

Lasik is performed in two steps.

The initial step is to create a flap of corneal tissue. This
process is achieved with a mechanical microkeratome using a metal blade, or
a femtosecond laser microkeratome that creates a series of tiny closely
arranged bubbles within the cornea. A hinge is left at one end of this flap.
The flap is folded back, revealing the stroma, the middle section of the
cornea. The process of lifting and folding back the flap can be
uncomfortable.

The second step of the procedure is to use an excimer laser (193 nm)
to remodel the corneal stroma. The laser vaporizes tissue in a finely
controlled manner without damaging adjacent stroma by releasing the
molecular bonds that hold the cells together. No burning with heat or actual
cutting is required to ablate the tissue. The layers of tissue removed are
tens of micrometers thick.

During the second step, the patient's vision will become very blurry once
the flap is lifted. He/she will be able to see only white light surrounding
the orange light of the laser. This can be disorienting.

Currently manufactured excimer lasers use a computer system that tracks the
patient's eye position up to 4,000 times per second, redirecting laser
pulses for precise placement. After the laser has reshaped the cornea, the
Lasik flap is repositioned over the treatment area by the surgeon. The flap
remains in position by natural adhesion until healing is completed.

Performing the laser ablation in the deeper corneal stroma typically
provides for more rapid visual recovery and less pain.